Synergistic water soluble preservative compositions of biocidal mixtures

ABSTRACT

A water soluble preservative antimicrobial composition for addition to commercial use products at predetermined use levels to provide synergistic biocidal activity against a wide range of fungi and gram-negative and gram-positive bacteria, comprising an active liquid blend of 
     (1) an admixture of 
     (a) one or more methylol compounds selected from the group consisting of N-[1,3-bis (hydroxymethyl)-2,5-dioxo-4-imidazolidinyl]-N,N&#39;-bis (hydroxymethyl) urea; 1,3-dimethylol-5,5-dimethyl hydantoin; sodium hydroxymethyl glycinate; 1,1-methylene bis[3-[3-(hydroxymethyl)-2,5-dioxo-4-imidazolidinyl]urea]; and glycine anhydride dimethylol; and 
     (b) 3-iodo-2-propynylbutyl carbamate, in a weight ratio of (a):(b) of 100:1 to 2000:1, and 
     (2) propylene glycol or 1,3-butylene glycol.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This application is a continuation-in-part of Ser. No. 08/234,089, filed Apr. 28, 1994, now U.S. Pat. No. 5,428,050.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to preservative compositions, and, more particularly, to a water soluble antibacterial compositions for addition to commercial use products to provide long time synergistic biocidal activity therein, which are active liquid blends of an admixture of a methylol compound and an iodopropynyl compound, in a predetermined weight ratio of 100:1 to 2000:1, and propylene glycol or 1,3-butylene glycol.

2. Description of the Prior Art

Combinations of antimicrobial agents have been developed in the prior art in order to:

(1) produce a biochemical synergism;

(2) broaden the antimicrobial spectrum of activity of each agent;

(3) increase water solubility for the admixture;

(4) minimize the toxicity or irritation of a given agent to the host; and

(5) minimize physical and chemical incompatibilities.

True biological synergism exists when two agents, when combined, require lesser amounts of the agents to bring about the same inhibitory or cidal effect than either single agent alone. While synergistic interaction for two or more antimicrobial agents does produce more than merely an additive effect in the resultant biological activity, in most cases the mechanism of such synergism remains a mystery.

M. Rosen et al., in U.S. Pat. No. 4,844,891, for example, described a preservative admixture of (a) a formaldehyde donor and (b) a halopropynyl compound, in a weight ratio of (a):(b) of 50:1 to 1:1, preferably 30:1 to 2:1, and, most preferably, 20:1 to 10:1, as providing fungicidal activity for 1-3 days in commercial use formulations. However, Rosen observed that when the ratio of (a):(b) in the concentrate exceeded 50:1 (System No. 16 in Table 1, a ratio of 73.33), the preservative composition was ineffective in providing biocidal protection in the use formulations. Thus a relatively large amount of the halopropynyl compound was required by Rosen to provide significant biocidal activity in the use composition. In such admixtures, although the formaldehyde donor is water soluble, the halopropynyl compound is substantially insoluble in water. Therefore it was difficult for Rosen to uniformly distribute his admixture throughout the use composition.

For these and other reasons, it is desired to provide a new and improved water soluble preservative admixture of such biocidal compounds which requires relatively little of the water insoluble and expensive halopropynyl compound, and that also provides effective synergistic protection in use formulations against a wide range of fungi and bacteria at different use levels over a long period of time.

A feature of the present invention is the provision of an admixture concentrate which is water soluble and which therefore can be uniformly distributed in use compositions at a predetermined use level.

Another feature herein is the provision of a preservative admixture which exhibits a long term synergistic biocidal activity against wide range of fungi and both gram-negative and gram-positive bacteria in the use compositions.

Still another feature of this invention is the provision of a water soluble preservative antibacterial composition for addition to commercial use products at predetermined use levels against a wide range of fungi and gram-negative and gram-positive bacteria, in the form of an active liquid blend of an admixture of one or more methylol compounds and an iodopropynyl compound, in a predetermined weight ratio of 100:1 to 2000:1, and propylene glycol or 1,3-butylene glycol.

These and other objects and features of the invention will be made apparent from the following more particular description of the invention.

SUMMARY OF THE INVENTION

What has been discovered is a water soluble preservative composition for addition to commercial use compositions at predetermined use levels, and uniformly distributed therein, which provides long term synergistic biocidal activity against a wide range of fungi and both gram-negative and gram-positive bacteria. The composition of the invention comprises:

(1) an admixture of powders of

(a) a methylol compound, or their equivalent, and

(b) iodopropynyl alcohol, or its ester, carbamate or ether derivative thereof,

in a weight ratio of (a):(b) of 100:1 to 2000:1, preferably 200:1 to 500:1; and

(2) propylene glycol or 1,3-butylene glycol.

Suitably, the composition of the invention comprises about 20 to 55 weight percent of (1) and 45-80 weight percent of (2), preferably 40 weight percent of (1) and 60 weight percent of (2).

Commercial use compositions containing about 0.1 to 5% by weight, preferably 0.5-1%, of the composition of the invention also are provided therein. Such use compositions contain an iodopropynyl compound in an amount necessary to provide the desired antifungal activity, and a methylol compound in an amount necessary to provide the desired antibacterial activity for the user.

DETAILED DESCRIPTION OF THE INVENTION

The invention is based upon the discoveries that in a predetermined admixture of (a) a methylol compound, or its equivalent, and (b) an iodopropynyl compound:

(1) Iodopropynyl compounds are substantially water insoluble at weight ratios of (a):(b) of less than 100; accordingly, at weight ratios below 100:1, it is difficult to uniformly distribute the iodopropynyl compound in aqueous use compositions, particularly in creams, gels and the like. In this invention, the admixtures are used at a weight ratio of (a):(b) of 100:1 to 2000:1, which are water soluble in all use compositions at conventional use levels.

(2) Effective synergistic biocidal activity is achieved for admixtures having a weight ratio of (a):(b) of 100:1 to 2000:1. Such admixtures have a Synergistic Index (SI) value approaching zero (maximum synergism) for a wide range of organisms. In contrast, admixtures with (a):(b) ratios below 100:1, e.g. 10:1 to 50:1, are much less synergistic, and are active with only a narrower range of organisms.

(3) A water soluble preservative antibacterial composition having enhanced activity can be made available in the form of a liquid blend of an admixture of one or more methyol compounds and 3-iodo-2-propynyl-butyl carbamate, in a weight ratio of 100:1 to 2000:1, and propylene glycol or 1,3-butylene glycol, in a predetermined formulation of 20-55 weight percent of the admixture and 45-80 weight percent of the glycol, preferably 40:60.

(4) Preservative activity for use compositions is achieved most effectively with an admixture wt. ratio of 100:1 to 2000:1 at use levels of the composition of 0.1 to 5%, preferably 0.5 to 1%, by weight of the finished product. In this amount, the antifungal iodopropynyl compound is present in a small amount which provides antifungal protection and which significantly reduces the cost and toxicity of the use composition, and the antibacterial methylol compound is present in an amount which is sufficient to provide the desired antibacterial protection.

The experimental results upon which these discoveries are based are described below. In these examples, the (a) methylol compound may be selected from diazolidinyl urea (GERMALL® II) N-[1,3-bis(hydroxy-methyl)-2,5-dioxo-4-imidazolidinyl]-N,N'-bis(hydroxymethyl) urea, imidurea (GERMALL® 115), 1,1-methylene bis[3-[3-(hydroxymethyl)-2,5-dioxo-4-imidazolidinyl]urea]; 1,3-dimethylol-5,5-dimethyl hydantoin (DMDMH), sodium hydroxymethyl glycinate (SUTTOCIDE® A), and glycine anhydride dimethylol (GADM); the (b) iodopropynyl compound is 3-iodo-2-propynylbutyl carbamate (IPBC); and the (c) glycol is propylene glycol or 1,3-butylene glycol.

1. Water Solubility

The water solubility or insolubility of admixtures of several methylol compounds with IPBC as 1% aqueous solutions is shown in Tables A through C below.

                  TABLE A                                                          ______________________________________                                         Weight Ratio of                                                                               Amount                                                          Germall ® II:IPBC                                                                         in ppm        Solubility                                        ______________________________________                                         2000:1          5            Soluble                                           1000:1          10           Soluble                                            500:1          20           Soluble                                            200:1          50           Soluble                                            100:1         100           Soluble                                            50:1          200           Insoluble                                          50:1          500           Insoluble                                         ______________________________________                                    

                  TABLE B                                                          ______________________________________                                         Weight Ratio of                                                                              Amount                                                           GADM:IPBC     in ppm         Solubility                                        ______________________________________                                         2000:1         5             Soluble                                           1000:1         10            Soluble                                            500:1         20            Soluble                                            200:1         50            Soluble                                            100:1        100            Soluble                                            50:1         200            Insoluble                                          20:1         500            Insoluble                                         ______________________________________                                    

                  TABLE C                                                          ______________________________________                                         Weight Ratio of                                                                              Amount                                                           DMDMH:IPBC    in ppm         Solubility                                        ______________________________________                                         2000:1         5             Soluble                                           1000:1         10            Soluble                                            500:1         20            Soluble                                            200:1         50            Soluble                                            100:1        100            Soluble                                            50:1         200            Insoluble                                          20:1         500            Insoluble                                         ______________________________________                                    

These results demonstrate that admixtures having a ratio of 50:1 or 20:1 are insoluble in water whereas at ratios of 100:1 to 2000:1 the admixtures are soluble in water.

2. SYNERGISM

Tables 1 through 14 below demonstrate the very effective synergistic interaction between compounds "a" and "b" against a broad range of fungi and both gram-negative and gram-positive bacteria. The following organisms were tested:

    ______________________________________                                                      ATCC                                                              Organism     Number   Inoculum Concentration                                   ______________________________________                                         Ps. aeruginosa (PSA)*                                                                        9027    2.1 × 10.sup.6 CFU/gm of Product                   E. coli (ECOLI)*                                                                             8739    4.7 × 10.sup.5 CFU/gm of Product                   Staph. aureus (SA)**                                                                         6538    1.6 × 10.sup.6 CFU/gm of Product                   Ps. cepacia (PC)*                                                                           25416    1.6 × 10.sup.6 CFU/gm of Product                   C. albicans (CAN)***                                                                        10231    8.0 × 10.sup.4 CFU/gm of Product                   A. niger (AN)***                                                                            16404    2.7 × 10.sup.5 CFU/gm of Product                   ______________________________________                                          TABLE D below lists the static (MIC) and cidal activities of several           antimicrobial agents in ppm. These activities are used to calculate the        Synergism Index (SI) of admixtures of the present invention.                   *gramnegative bacteria                                                         **grampositive bacteria                                                        ***fungi                                                                 

                                      TABLE D                                      __________________________________________________________________________     Organism                                                                       (ATCC #) IPBC  Germall ® II                                                                      GADM   DMDMH  IPIGA                                      __________________________________________________________________________     (SA) (6538)                                                                             100/200                                                                               400/1600                                                                             400/800                                                                                450/1600                                                                              300/5000                                  (ECOLI) (8739)                                                                           50/100                                                                               400/1600                                                                             400/800                                                                               400/800                                                                               150/600                                    (PSA) (9027)                                                                             800/1200                                                                             400/1600                                                                             400/400                                                                                600/1600                                                                             70/70                                      (PC) (25416)                                                                            1200/1800                                                                            200/400                                                                               200/400                                                                                600/1600                                                                              70/300                                    (CAN) (10231)                                                                            50/100                                                                               1500/15000                                                                            7500/15000                                                                            8000/16000                                                                            50/300                                    (AN) (16404)                                                                             50/100                                                                              3200/3200                                                                             1600/3200                                                                              8000/16000                                                                           30/30                                      __________________________________________________________________________

The Synergism Index was determined by the same mathematical treatment of such data described by Kull et al. in Applied Microbiology 9,538-541 (1961) using the following relationship: ##EQU1## where: 1. Q_(a) =The quantity of Compound a acting alone, producing an endpoint.

2. Q_(b) =The quantity of Compound b acting alone, producing and endpoint.

3. Q^(A) =The quantity of Compound A in mixture, producing an endpoint.

4. Q_(B) =The quantity of Compound B in mixture, producing an endpoint.

When SI is equal to 1, a mere additive effect of the components in the mixture is indicated; when SI is less than 1, synergism has occurred; and when SI is greater than 1 it indicates antagonism of the two components.

According to this well known method of measuring synergism, the quantity of each component in the various mixtures is compared with the quantity of pure component that is required to reach the same endpoint or to produce the same microbiological effect as the mixture.

                  TABLE 1                                                          ______________________________________                                         2000:1 Wt. Ratio GERMALL ® II/IPBC                                         Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  0.05  99.95 0.06                                "       ECOLI    100     1600  0.05  99.95 0.06                                "       PSA      1200    1600  0.05  99.95 0.06                                "       PC       1800    1250  0.05  99.95 0.08                                "       CAN      100     15000 0.05  99.95 0.01                                "       AN       100     3200  0.05  99.95 0.03                                0.025%  SA       200     1600  0.125 249.9 0.16                                "       ECOLI    100     1600  0.125 249.9 0.16                                "       PSA      1200    1600  0.125 249.9 0.16                                "       PC       1800    1250  0.125 249.9 0.20                                "       CAN      100     15000 0.125 249.9 0.02                                "       AN       100     3200  0.125 249.9 0.08                                0.05%   SA       200     1600  0.25  499.8 0.31                                "       ECOLI    100     1600  0.25  499.8 0.31                                "       PSA      1200    1600  0.25  499.8 0.31                                "       PC       1800    1250  0.25  499.8 0.40                                "       CAN      100     15000 0.25  499.8 0.04                                "       AN       100     3200  0.25  499.8 0.16                                0.10%   SA       200     1600  0.5   999.5 0.63                                "       ECOLI    100     1600  0.5   999.5 0.63                                "       PSA      1200    1600  0.5   999.5 0.63                                "       PC       1800    1250  0.5   999.5 0.80                                "       CAN      100     15000 0.5   999.5 0.07                                "       AN       100     3200  0.5   999.5 0.32                                0.20%   SA       200     1600  1     1999  1.25                                "       ECOLI    100     1600  1     1999  1.26                                "       PSA      1200    1600  1     1999  1.25                                "       PC       1800    1250  1     1999  1.60                                "       CAN      100     15000 1     1999  0.14                                "       AN       100     3200  1     1999  0.63                                0.40%   SA       200     1600  2     3998  2.51                                "       ECOLI    100     1600  2     3998  2.52                                "       PSA      1200    1600  2     3998  2.50                                "       PC       1800    1250  2     3998  3.20                                "       CAN      100     15000 2     3998  0.29                                "       AN       100     3200  2     3998  1.27                                0.50%   SA       200     1600  2.5   4997.5                                                                               3.14                                "       ECOLI    100     1600  2.5   4997.5                                                                               3.15                                "       PSA      1200    1600  2.5   4997.5                                                                               3.13                                "       PC       1800    1250  2.5   4997.5                                                                               4.00                                "       CAN      100     15000 2.5   4997.5                                                                               0.36                                "       AN       100     3200  2.5   4997.5                                                                               1.59                                ______________________________________                                    

                  TABLE 2                                                          ______________________________________                                         1000:1 Wt. Ratio GERMALL ® II/IPBC                                         Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  0.1   99.9  0.06                                "       ECOLI    100     1600  0.1   99.9  0.06                                "       PSA      1200    1600  0.1   99.9  0.06                                "       PC       1800    1250  0.1   99.9  0.08                                "       CAN      100     15000 0.1   99.9  0.01                                "       AN       100     3200  0.1   99.9  0.03                                0.025%  SA       200     1600  0.25  249.8 0.16                                "       ECOLI    100     1600  0.25  249.8 0.16                                "       PSA      1200    1600  0.25  249.8 0.16                                "       PC       1800    1250  0.25  249.8 0.20                                "       CAN      100     15000 0.25  249.8 0.02                                "       AN       100     3200  0.25  249.8 0.08                                0.05%   SA       200     1600  0.5   499.5 0.31                                "       ECOLI    100     1600  0.5   499.5 0.32                                "       PSA      1200    1600  0.5   499.5 0.31                                "       PC       1800    1250  0.5   499.5 0.40                                "       CAN      100     15000 0.5   499.5 0.04                                "       AN       100     3200  0.5   499.5 0.16                                0.10%   SA       200     1600  1     999   0.63                                "       ECOLI    100     1600  1     999   0.63                                "       PSA      1200    1600  1     999   0.63                                "       PC       1800    1250  1     999   0.80                                "       CAN      100     15000 1     999   0.08                                "       AN       100     3200  1     999   0.32                                0.20%   SA       200     1600  2     1998  1.26                                "       ECOLI    100     1600  2     1998  1.27                                "       PSA      1200    1600  2     1998  1.25                                "       PC       1800    1250  2     1998  1.60                                "       CAN      100     15000 2     1998  0.15                                "       AN       100     3200  2     1998  0.64                                0.40%   SA       200     1600  4     3996  2.52                                "       ECOLI    100     1600  4     3996  2.54                                "       PSA      1200    1600  4     3996  2.50                                "       PC       1800    1250  4     3996  3.20                                "       CAN      100     15000 4     3996  0.31                                "       AN       100     3200  4     3996  1.29                                0.50%   SA       200     1600  5     4995  3.15                                "       ECOLI    100     1600  5     4995  3.17                                "       PSA      1200    1600  5     4995  3.13                                "       PC       1800    1250  5     4995  4.00                                "       CAN      100     15000 5     4995  0.38                                "       AN       100     3200  5     4995  1.61                                ______________________________________                                    

                  TABLE 3                                                          ______________________________________                                         500:1 Wt. Ratio GERMALL ® II/IPBC                                          Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  0.2   99.8  0.06                                "       ECOLI    100     1600  0.2   99.8  0.06                                "       PSA      1200    1600  0.2   99.8  0.06                                "       PC       1800    1250  0.2   99.8  0.08                                "       CAN      100     15000 0.2   99.8  0.01                                "       AN       100     3200  0.2   99.8  0.03                                0.025%  SA       200     1600  0.5   249.5 0.16                                "       ECOLI    100     1600  0.5   249.5 0.16                                "       PSA      1200    1600  0.5   249.5 0.16                                "       PC       1800    1250  0.5   249.5 0.20                                "       CAN      100     15000 0.5   249.5 0.02                                "       AN       100     3200  0.5   249.5 0.08                                0.05%   SA       200     1600  1     499   0.32                                "       ECOLI    100     1600  1     499   0.32                                "       PSA      1200    1600  1     499   0.31                                "       PC       isoo    1250  1     499   0.40                                "       CAN      100     15000 1     499   0.04                                "       AN       100     3200  1     499   0.17                                0.10%   SA       200     1600  2     998   0.63                                "       ECOLI    100     1600  2     998   0.64                                "       PSA      1200    1600  2     998   0.63                                "       PC       1800    1250  2     998   0.80                                "       CAN      100     15000 2     998   0.09                                "       AN       100     3200  2     998   0.33                                0.20%   SA       200     1600  4     1996  1.27                                "       ECOLI    100     1600  4     1996  1.29                                "       PSA      1200    1600  4     1996  1.25                                "       PC       1800    1250  4     1996  1.60                                "       CAN      100     15000 4     1996  0.17                                "       AN       100     3200  4     1996  0.66                                0.40%   SA       200     1600  8     3992  2.54                                "       ECOLI    100     1600  8     3992  2.58                                "       PSA      1200    1600  8     3992  2.50                                "       PC       1800    1250  8     3992  3.20                                "       CAN      100     15000 8     3992  0.35                                "       AN       100     3200  8     3992  1.33                                0.50%   SA       200     1600  10    4990  3.17                                "       ECOLI    100     1600  10    4990  3.22                                "       PSA      1200    1600  10    4990  3.13                                "       PC       1800    1250  10    4990  4.00                                "       CAN      100     15000 10    4990  0.43                                "       AN       100     3200  10    4990  1.66                                ______________________________________                                    

                  TABLE 4                                                          ______________________________________                                         200:1 Wt. Ratio GERMALL ® II/IPBC                                          Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  0.5   99.5  0.06                                "       ECOLI    100     1600  0.5   99.5  0.07                                "       PSA      1200    1600  0.5   99.5  0.06                                "       PC       1800    1250  0.5   99.5  0.08                                "       CAN      100     15000 0.5   99.5  0.01                                "       AN       100     3200  0.5   99.5  0.04                                0.025%  SA       200     1600  1.25  248.75                                                                               0.16                                "       ECOLI    100     1600  1.25  248.75                                                                               0.17                                "       PSA      1200    1600  1.25  248.75                                                                               0.16                                "       PC       1800    1250  1.25  248.75                                                                               0.20                                "       CAN      100     15000 1.25  248.75                                                                               0.03                                "       AN       100     3200  1.25  248.75                                                                               0.09                                0.05%   SA       200     1600  2.5   497.5 0.32                                "       ECOLI    100     1600  2.5   497.5 0.34                                "       PSA      1200    1600  2.5   497.5 0.31                                "       PC       1800    1250  2.5   497.5 0.40                                "       CAN      100     15000 2.5   497.5 0.06                                "       AN       100     3200  2.5   497.5 0.18                                0.10%   SA       200     1600  5     995   0.65                                "       ECOLI    100     1600  5     995   0.67                                "       PSA      1200    1600  5     995   0.63                                "       PC       1800    1250  5     995   0.80                                "       CAN      100     15000 5     995   0.12                                "       AN       100     3200  5     995   0.36                                0.20%   SA       200     1600  10    1990  1.29                                "       ECOLI    100     1600  10    1990  1.34                                "       PSA      1200    1600  10    1990  1.25                                "       PC       1800    1250  10    1990  1.60                                "       CAN      100     15000 10    1990  0.23                                "       AN       100     3200  10    1990  0.72                                0.40%   SA       200     1600  20    3980  2.59                                "       ECOLI    100     1600  20    3980  2.69                                "       PSA      1200    1600  20    3980  2.50                                "       PC       1800    1250  20    3980  3.20                                "       CAN      100     15000 20    3980  0.47                                "       AN       100     3200  20    3980  1.44                                0.50%   SA       200     1600  25    4975  3.23                                "       ECOLI    100     1600  25    4975  3.36                                "       PSA      1200    1600  25    4975  3.13                                "       PC       1800    1250  25    4975  3.99                                "       CAN      100     15000 25    4975  0.58                                "       AN       100     3200  25    4975  1.80                                ______________________________________                                    

                  TABLE 5                                                          ______________________________________                                         100:1 Wt. Ratio GERMALL ® II/IPBC                                          Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  1     99    0.07                                "       ECOLI    100     1600  1     99    0.07                                "       PSA      1200    1600  1     99    0.06                                "       PC       1800    1250  1     99    0.08                                "       CAN      100     15000 1     99    0.02                                "       AN       100     3200  1     99    0.04                                0.025%  SA       200     1600  2.5   248   0.17                                "       ECOLI    100     1600  2.5   248   0.18                                "       PSA      1200    1600  2.5   248   0.16                                "       PC       1800    1250  2.5   248   0.20                                "       CAN      100     15000 2.5   248   0.04                                "       AN       100     3200  2.5   248   0.10                                0.05%   SA       200     1600  5     495   0.33                                "       ECOLI    100     1600  5     495   0.36                                "       PSA      1200    1600  5     495   0.31                                "       PC       1800    1250  5     495   0.40                                "       CAN      100     15000 5     495   0.08                                "       AN       100     3200  5     495   0.20                                0.10%   SA       200     1600  10    990   0.67                                "       ECOLI    100     1600  10    990   0.72                                "       PSA      1200    1600  10    990   0.63                                "       PC       1800    1250  10    990   0.80                                "       CAN      100     15000 10    990   0.17                                "       AN       100     3200  10    990   0.41                                0.20%   SA       200     1600  20    1980  1.34                                "       ECOLI    100     1600  20    1980  1.44                                "       PSA      1200    1600  20    1980  1.25                                "       PC       1800    1250  20    1980  1.60                                "       CAN      100     15000 20    1980  0.33                                "       AN       100     3200  20    1980  0.82                                0.40%   SA       200     1600  40    3960  2.68                                "       ECOLI    100     1600  40    3960  2.88                                "       PSA      1200    1600  40    3960  2.51                                "       PC       1800    1250  40    3960  3.19                                "       CAN      100     15000 40    3960  0.66                                "       AN       100     3200  40    3960  1.64                                0.50%   SA       200     1600  50    4950  3.34                                "       ECOLI    100     1600  50    4950  3.59                                "       PSA      1200    1600  50    4950  3.14                                "       PC       1800    1250  50    4950  3.99                                "       CAN      100     15000 50    4950  0.83                                "       AN       100     3200  50    4950  2.05                                ______________________________________                                    

                  TABLE 6                                                          ______________________________________                                         50:1 Wt. Ratio GERMALL ® II/IPBC                                           Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  2     98    0.07                                "       ECOLI    100     1600  2     98    0.08                                "       PSA      1200    1600  2     98    0.06                                "       PC       1800    1250  2     98    0.08                                "       CAN      100     15000 2     98    0.03                                "       AN       100     3200  2     98    0.05                                0.025%  SA       200     1600  5     245   0.18                                "       ECOLI    100     1600  5     245   0.20                                "       PSA      1200    1600  5     245   0.16                                "       PC       1800    1250  5     245   0.20                                "       CAN      100     15000 5     245   0.07                                "       AN       100     3200  5     245   0.13                                0.05%   SA       200     1600  10    490   0.36                                "       ECOLI    100     1600  10    490   0.41                                "       PSA      1200    1600  10    490   0.31                                "       PC       1800    1250  10    490   0.40                                "       CAN      100     15000 10    490   0.13                                "       AN       100     3200  10    490   0.25                                0.10%   SA       200     1600  20    980   0.71                                "       ECOLI    100     1600  20    980   0.81                                "       PSA      1200    1600  20    980   0.63                                "       PC       1800    1250  20    980   0.80                                "       CAN      100     15000 20    980   0.27                                "       AN       100     3200  20    980   0.51                                0.20%   SA       200     1600  40    1960  1.43                                "       ECOLI    100     1600  40    1960  1.63                                "       PSA      1200    1600  40    1960  1.26                                "       PC       1800    1250  40    1960  1.59                                "       CAN      100     15000 40    1960  0.53                                "       AN       100     3200  40    1960  1.01                                0.40%   SA       200     1600  80    3920  2.85                                "       ECOLI    100     1600  80    3920  3.25                                "       PSA      1200    1600  80    3920  2.52                                "       PC       1800    1250  80    3920  3.18                                "       CAN      100     15000 80    3920  1.06                                "       AN       100     3200  80    3920  2.03                                0.50%   SA       200     1600  100   4900  3.56                                "       ECOLI    100     1600  100   4900  4.06                                "       PSA      1200    1600  100   4900  3.15                                "       PC       1800    1250  100   4990  3.98                                "       CAN      100     15000 100   4900  1.33                                "       AN       100     3200  100   4900  2.53                                ______________________________________                                    

                  TABLE 7                                                          ______________________________________                                         20:1 Wt. Ratio GERMALL ® II/IPBC                                           Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  5     95    0.08                                "       ECOLI    100     1600  5     95    0.11                                "       PSA      1200    1600  5     95    0.06                                "       PC       1800    1250  5     95    0.08                                "       CAN      100     15000 5     95    0.06                                "       AN       100     3200  5     95    0.08                                0.025%  SA       200     1600  12.5  237.5 0.21                                "       ECOLI    100     1600  12.5  237.5 0.27                                "       PSA      1200    1600  12.5  237.5 0.16                                "       PC       1800    1250  12.5  237.5 0.20                                "       CAN      100     15000 12.5  237.5 0.14                                "       AN       100     3200  12.5  237.5 0.20                                0.05%   SA       200     1600  25    475   0.42                                "       ECOLI    100     1600  25    475   0.55                                "       PSA      1200    1600  25    475   0.32                                "       PC       1800    1250  25    475   0.39                                "       CAN      100     15000 25    475   0.28                                "       AN       100     3200  25    475   0.40                                0.10%   SA       200     1600  50    950   0.84                                "       ECOLI    100     1600  50    950   1.09                                "       PSA      1200    1600  50    950   0.64                                "       PC       1800    1250  50    950   0.79                                "       CAN      100     15000 50    950   0.56                                "       AN       100     3200  50    950   0.80                                0.20%   SA       200     1600  100   1900  1.69                                "       ECOLI    100     1600  100   1900  2.19                                "       PSA      1200    1600  100   1900  1.27                                "       PC       1800    1250  100   1900  1.58                                "       CA.N     100     15000 100   1900  1.13                                "       AN       100     3200  100   1900  1.59                                0.40%   SA       200     1600  200   4800  4.00                                "       ECOLI    100     1600  200   4800  5.00                                "       PSA      1200    1600  200   4800  3.17                                "       PC       1800    1250  200   4800  3.95                                "       CAN      100     15000 200   4800  2.32                                "       AN       100     3200  200   4800  3.50                                0.50%   SA       200     1600  250   4750  4.22                                "       ECOLI    100     1600  250   4750  5.47                                "       PSA      1200    1600  250   4750  3.18                                "       PC       1800    1250  250   4750  3.94                                "       CAN      100     15000 250   4750  2.82                                "       AN       100     3200  250   4750  3.98                                ______________________________________                                    

                  TABLE 8                                                          ______________________________________                                         2000:1 Wt. Ratio DMDMH/IPBC                                                    Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  0.05  99.95 0.06                                "       ECOLI    100     800   0.05  99.95 0.13                                "       PSA      1200    1600  0.05  99.95 0.06                                "       PC       1800    1600  0.05  99.95 0.06                                "       CAN      100     16000 0.05  99.95 0.01                                "       AN       100     16000 0.05  99.95 0.01                                0.025%  SA       200     1600  0.125 249.88                                                                               0.16                                "       ECOLI    100     800   0.125 249.88                                                                               0.31                                "       PSA      1200    1600  0.125 249.88                                                                               0.16                                "       PC       1800    1600  0.125 249.88                                                                               0.16                                "       CAN      100     16000 0.125 249.88                                                                               0.02                                "       AN       100     16000 0.125 249.88                                                                               0.02                                0.05%   SA       200     1600  0.25  499.75                                                                               0.31                                "       ECOLI    100     800   0.25  499.75                                                                               0.63                                "       PSA      1200    1600  0.25  499.75                                                                               0.31                                "       PC       1800    1600  0.25  499.75                                                                               0.31                                "       CAN      100     16000 0.25  499.75                                                                               0.03                                "       AN       100     16000 0.25  499.75                                                                               0.03                                0.10%   SA       200     1600  0.5   999.5 0.63                                "       ECOLI    100     800   0.5   999.5 1.25                                "       PSA      1200    1600  0.5   999.5 0.63                                "       PC       1800    1600  0.5   999.5 0.62                                "       CAN      100     16000 0.5   999.5 0.07                                "       AN       100     16000 0.5   999.5 0.07                                0.20%   SA       200     1600  1     1999  1.25                                "       ECOLI    100     800   1     1999  2.51                                "       PSA      1200    1600  1     1999  1.25                                "       PC       1800    1600  1     1999  1.25                                "       CAN      100     16000 1     1999  0.13                                "       AN       100     16000 1     1999  0.13                                0.40%   SA       200     1600  2     3998  2.51                                "       ECOLI    100     800   2     3998  5.02                                "       PSA      1200    1600  2     3998  2.50                                "       PC       1800    1600  2     3998  2.50                                "       CAN      100     16000 2     3998  0.27                                "       AN       100     16000 2     3998  0.27                                0.50%   SA       200     1600  2.5   4997.5                                                                               3.14                                "       ECOLI    100     800   2.5   4997.5                                                                               6.27                                "       PSA      1200    1600  2.5   4997.5                                                                               3.13                                "       PC       1800    1600  2.5   4997.5                                                                               3.12                                "       CAN      100     16000 2.5   4997.5                                                                               0.34                                ""      AN       100     16000 2.5   4997.5                                                                               0.34                                ______________________________________                                    

                  TABLE 9                                                          ______________________________________                                         1000:1 Wt. Ratio DMDMH/IPBC                                                    Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  0.1   99.9  0.06                                "       ECOLI    100     800   0.1   99.9  0.13                                "       PSA      1200    1600  0.1   99.9  0.06                                "       PC       1800    1600  0.1   99.9  0.06                                "       CAN      100     16000 0.1   99.9  0.01                                "       AN       100     16000 0.1   99.9  0.01                                0.025%  SA       200     1600  0.25  249.8 0.16                                "       ECOLI    100     800   0.25  249.8 0.31                                "       PSA      1200    1600  0.25  249.8 0.16                                "       PC       1800    1600  0.25  249.8 0.16                                "       CAN      100     16000 0.25  249.8 0.02                                "       AN       100     16000 0.25  249.8 0.02                                0.05%   SA       200     1600  0.5   499.5 0.31                                "       ECOLI    100     800   0.5   499.5 0.63                                "       PSA      1200    1600  0.5   499.5 0.31                                "       PC       1800    1600  0.5   499.5 0.31                                "       CAN      100     16000 0.5   499.5 0.04                                "       AN       100     16000 0.5   499.5 0.04                                0.10%   SA       200     1600  1     999   0.63                                "       ECOLI    100     800   1     999   1.26                                "       PSA      1200    1600  1     999   0.63                                "       PC       1800    1600  1     999   0.62                                "       CAN      100     16000 1     999   0.07                                "       AN       100     16000 1     999   0.07                                0.20%   SA       200     1600  2     1998  1.26                                "       ECOLI    100     800   2     1998  2.52                                "       PSA      1200    1600  2     1998  1.25                                "       PC       1800    1600  2     1998  1.25                                "       CAN      100     16000 2     1998  0.14                                "       AN       100     16000 2     1998  0.14                                0.40%   SA       200     1600  4     3996  2.52                                "       ECOLI    100     800   4     3996  5.04                                "       PSA      1200    1600  4     3996  2.50                                "       PC       1800    1600  4     3996  2.50                                "       CAN      100     16000 4     3996  0.29                                "       AN       100     16000 4     3996  0.29                                0.50%   SA       200     1600  5     4995  3.15                                "       ECOLI    100     800   5     4995  6.29                                "       PSA      1200    1600  5     4995  3.13                                "       PC       1800    1600  5     4995  3.12                                "       CAN      100     16000 5     4995  0.36                                "       AN       100     16000 2.5   4997.5                                                                               0.36                                ______________________________________                                    

                  TABLE 10                                                         ______________________________________                                         500:1 Wt. Ratio DMDMH/IPBC                                                     Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  0.2   99.8  0.06                                "       ECOLI    100     800   0.2   99.8  0.13                                "       PSA      1200    1600  0.2   99.8  0.06                                "       PC       1800    1600  0.2   99.8  0.06                                "       CAN      100     16000 0.2   99.8  0.01                                "       AN       100     16000 0.2   99.8  0.01                                0.25%   SA       200     1600  0.5   249.5 0.16                                "       ECOLI    100     800   0.5   249.5 0.32                                "       PSA      1200    1600  0.5   249.5 0.16                                "       PC       1800    1600  0.5   249.5 0.16                                "       CAN      100     16000 0.5   249.5 0.02                                "       AN       100     16000 0.5   249.5 0.02                                0.05%   SA       200     1600  1     499   0.32                                "       ECOLI    100     800   1     499   0.63                                "       PSA      1200    1600  1     499   0.31                                "       PC       1800    1600  1     499   0.31                                "       CAN      100     16000 1     499   0.04                                "       AN       100     16000 1     499   0.04                                0.10%   SA       200     1600  2     998   0.63                                "       ECOLI    100     800   2     998   1.27                                "       PSA      1200    1600  2     998   0.63                                "       PC       1800    1600  2     998   0.62                                "       CAN      100     16000 2     998   0.08                                "       AN       100     16000 2     998   0.08                                0.20%   SA       200     1600  4     1996  1.27                                "       ECOLI    100     800   4     1996  2.54                                "       PSA      1200    1600  4     1996  1.25                                "       PC       1800    1600  4     1996  1.25                                "       CAN      100     16000 4     1996  0.16                                "       AN       100     16000 4     1996  0.16                                0.40%   SA       200     1600  8     3992  2.54                                "       ECOLI    100     800   8     3992  5.07                                "       PSA      1200    1600  8     3992  2.50                                "       PC       1800    1600  8     3992  2.50                                "       CAN      100     16000 8     3992  0.33                                "       AN       100     16000 8     3992  0.33                                0.50%   SA       200     1600  10    4900  3.11                                "       ECOLI    100     800   10    4900  6.23                                "       PSA      1200    1600  10    4900  3.07                                "       PC       1800    1600  10    4900  3.07                                "       CAN      100     16000 10    4900  0.41                                "       AN       100     16000 10    4900  0.41                                ______________________________________                                    

                  TABLE 11                                                         ______________________________________                                         200:1 Wt. Ratio DMDMH/IPBC                                                     Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  0.5   99.5  0.06                                "       ECOLI    100     800   0.5   99.5  0.13                                "       PSA      1200    1600  0.5   99.5  0.06                                "       PC       1800    1600  0.5   99.5  0.06                                "       CAN      100     16000 0.5   99.5  0.01                                "       AN       100     16000 0.5   99.5  0.01                                0.025%  SA       200     1600  1.25  248.75                                                                               0.16                                "       ECOLI    100     800   1.25  248.75                                                                               0.32                                "       PSA      1200    1600  1.25  248.75                                                                               0.16                                "       PC       1800    1600  1.25  248.75                                                                               0.16                                "       CAN      100     16000 1.25  248.75                                                                               0.03                                "       AN       100     16000 1.25  248.75                                                                               0.03                                0.05%   SA       200     1600  2.5   497.5 0.32                                "       ECOLI    100     800   2.5   497.5 0.65                                "       PSA      1200    1600  2.5   497.5 0.31                                "       PC       1800    1600  2.5   497.5 0.31                                "       CAN      100     16000 2.5   497.5 0.06                                "       AN       100     16000 2.5   497.5 0.06                                0.10%   SA       200     1600  5     995   0.65                                "       ECOLI    100     800   5     995   1.29                                "       PSA      1200    1600  5     995   0.63                                "       PC       1800    1600  5     995   0.62                                "       CAN      100     16000 5     995   0.11                                "       AN       100     16000 5     995   0.11                                0.20%   SA       200     1600  10    1990  1.29                                "       ECOLI    100     800   10    1990  2.59                                "       PSA      1200    1600  10    1990  1.25                                "       PC       1800    1600  10    1990  1.25                                "       CAN      100     16000 10    1990  0.22                                "       AN       100     16000 10    1990  0.22                                0.40%   SA       200     1600  20    3980  2.59                                "       ECOLI    100     800   20    3980  5.18                                "       PSA      1200    1600  20    3980  2.50                                "       PC       1800    1600  20    3980  2.50                                "       CAN      100     16000 20    3980  0.45                                "       AN       100     16000 20    3980  0.45                                0.50%   SA       200     1600  25    4975  3.23                                "       ECOLI    100     800   25    4975  6.47                                "       PSA      1200    1600  25    4975  3.13                                "       PC       1800    1600  25    4975  3.12                                "       CAN      100     16000 25    4975  0.56                                "       AN       100     16000 25    4975  0.56                                ______________________________________                                    

                  TABLE 12                                                         ______________________________________                                         100:1 Wt. Ratio DMDMH/IPBC                                                     Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  1     99    0.07                                "       ECOLI    100     800   1     99    0.13                                "       PSA      1200    1600  1     99    0.06                                "       PC       1800    1600  1     99    0.06                                "       CAN      100     16000 1     99    0.02                                "       AN       100     16000 1     99    0.02                                0.025%  SA       200     1600  2.5   248   0.17                                "       ECOLI    100     800   2.5   248   0.33                                "       PSA      1200    1600  2.5   248   0.16                                "       PC       1800    1600  2.5   248   0.16                                "       CAN      100     16000 2.5   248   0.04                                "       AN       100     16000 2.5   248   0.04                                0.05%   SA       200     1600  5     495   0.33                                "       ECOLI    100     800   5     495   0.67                                "       PSA      1200    1600  5     495   0.31                                "       PC       1800    1600  5     495   0.31                                "       CAN      100     16000 5     495   0.08                                "       AN       100     16000 5     495   0.08                                0.10%   SA       200     1600  10    990   0.67                                "       ECOLI    100     800   10    990   1.34                                "       PSA      1200    1600  10    990   0.63                                "       PC       1800    1600  10    990   0.62                                "       CAN      100     16000 10    990   0.16                                "       AN       100     16000 10    990   0.16                                0.20%   SA       200     1600  20    1980  1.34                                "       ECOLI    100     800   20    1980  2.68                                "       PSA      1200    1600  20    1980  1.25                                "       PC       1800    1600  20    1980  1.25                                "       CAN      100     16000 20    1980  0.32                                "       AN       100     16000 20    1980  0.32                                0.40%   SA       200     1600  40    3960  2.68                                "       ECOLI    100     800   40    3960  5.35                                "       PSA      1200    1600  40    3960  2.51                                "       PC       1800    1600  40    3960  2.50                                "       CAN      100     16000 40    3960  0.65                                "       AN       100     16000 40    3960  0.65                                0.50%   SA       200     1600  50    4950  3.34                                "       ECOLI    100     800   50    4950  6.69                                "       PSA      1200    1600  50    4950  3.14                                "       PC       1800    1600  50    4950  3.12                                "       CAN      100     16000 50    4950  0.81                                "       AN       100     16000 50    4950  0.81                                ______________________________________                                    

                  TABLE 13                                                         ______________________________________                                         50:1 Wt. Ratio DMDMH/IPBC                                                      Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  2     98    0.07                                0.01%   SA       200     1600  2     98    0.07                                "       ECOLI    100     800   2     98    0.14                                "       PSA      1200    1600  2     98    0.06                                "       PC       1800    1600  2     98    0.06                                "       CAN      100     16000 2     98    0.03                                "       AN       100     16000 2     98    0.03                                0.025%  SA       200     1600  5     245   0.18                                "       ECOLI    100     800   5     245   0.36                                "       PSA      1200    1600  5     245   0.16                                "       PC       1800    1600  5     245   0.16                                "       CAN      100     16000 5     245   0.07                                "       AN       100     16000 5     245   0.07                                0.05%   SA       200     1600  10    490   0.36                                "       ECOLI    100     800   10    490   0.71                                "       PSA      1200    1600  10    490   0.31                                "       PC       1800    1600  10    490   0.31                                "       CAN      100     16000 10    490   0.13                                "       AN       100     16000 10    490   0.13                                0.10%   SA       200     1600  20    980   0.71                                "       ECOLI    100     800   20    980   1.43                                "       PSA      1200    1600  20    980   0.63                                "       PC       1800    1600  20    980   0.62                                "       CAN      100     16000 20    980   0.26                                "       AN       100     16000 20    980   0.26                                0.20%   SA       200     1600  40    1960  1.43                                "       ECOLI    100     800   40    1960  2.85                                "       PSA      1200    1600  40    1960  1.26                                "       PC       1800    1600  40    1960  1.25                                "       CAN      100     16000 40    1960  0.52                                "       AN       100     16000 40    1960  0.52                                0.40%   SA       200     1600  80    3920  2.85                                "       ECOLI    100     800   80    3920  5.70                                "       PSA      1200    1600  80    3920  2.52                                "       PC       1800    1600  80    3920  2.49                                "       CAN      100     16000 80    3920  1.05                                "       AN       100     16000 80    3920  1.05                                0.50%   SA       200     1600  100   4900  3.56                                "       ECOLI    100     800   100   4900  7.13                                "       PSA      1200    1600  100   4900  3.15                                "       PC       1800    1600  100   4900  3.12                                "       CAN      100     16000 100   4900  1.31                                "       AN       100     16000 100   4900  1.31                                ______________________________________                                    

                  TABLE 14                                                         ______________________________________                                         20:1 Wt. Ratio DMDMH/IPBC                                                      Use Level                                                                              Organism Q.sub.a Q.sub.b                                                                              Q.sub.A                                                                              Q.sub.B                                                                              SI                                  ______________________________________                                         0.01%   SA       200     1600  5     95    0.08                                "       ECOLI    100     800   5     95    0.17                                "       PSA      1200    1600  5     95    0.06                                "       PC       1800    1600  5     95    0.06                                "       CAN      100     16000 5     95    0.06                                "       AN       100     16000 5     95    0.06                                0.025%  SA       200     1600  12.5  237.5 0.21                                "       ECOLI    100     800   12.5  237.5 0.42                                "       PSA      1200    1600  12.5  237.5 0.16                                "       PC       1800    1600  12.5  237.5 0.16                                "       CAN      100     16000 12.5  237.5 0.14                                "       AN       100     16000 12.5  237.5 0.14                                0.05%   SA       200     1600  25    475   0.42                                "       ECOLI    100     800   25    475   0.84                                "       PSA      1200    1600  25    475   0.32                                "       PC       1800    1600  25    475   0.31                                "       CAN      100     16000 25    475   0.28                                "       AN       100     16000 25    475   0.28                                0.10%   SA       200     1600  50    950   0.84                                "       ECOLI    100     800   50    950   1.69                                "       PSA      1200    1600  50    950   0.64                                "       PC       1800    1600  50    950   0.62                                "       CAN      100     16000 50    950   0.56                                "       AN       100     16000 50    950   0.56                                0.20%   SA       200     1600  100   1900  1.69                                "       ECOLI    100     800   100   1900  3.38                                "       PSA      1200    1600  100   1900  1.27                                "       PC       1800    1600  100   1900  1.24                                "       CAN      100     16000 100   1900  1.12                                "       AN       100     16000 100   1900  1.12                                0.40%   SA       200     1600  200   4800  4.00                                "       ECOLI    100     800   200   4800  8.00                                "       PSA      1200    1600  200   4800  3.17                                "       PC       1800    1600  200   4800  3.11                                "       CAN      100     16000 200   4800  2.30                                "       AN       100     16000 200   4800  2.30                                0.50%   SA       200     1600  250   4750  4.22                                "       ECOLI    100     800   250   4750  8.44                                "       PSA      1200    1600  250   4750  3.18                                "       PC       1800    1600  250   4750  3.11                                "       CAN      100     16000 250   4750  2.80                                "       AN       100     16000 250   4750  2.80                                ______________________________________                                    

Similar SI results also were found with GADM and SUTTOCIDE® A as the methylol compound in place of Germall® II or DMDMH in admixtures with IPBC over the same wt. ratios and use level ranges as shown in the Tables 1-14 above.

Tables 1 through 14 above illustrate the synergism of IPBC (compound B) with Germall® II or DMDMH (compound A) at weight ratios of A:B of 2000:1, 1000:1, 500:1, 200:1, 100:1, 50:1 and 20:1. Synergism is very effective for all ratios at low use levels, e.g. 0.01% to 0.1%, against all tested gram-positive, gram-negative organisms and fungi organisms. At slightly higher use concentrations, e.g. 0.20 to 0.50%, all tested ratios were synergistic against Candida albicans and A. niger also. However, at 50:1 and 20:1 ratios, the synergistic effect is negligible at the 0.01 to 0.1% use levels, and non-synergistic even against Candida albicans and A. niger at use levels of 0.20 to 0.50%.

The SI values were lower for Germall® II as the methylol compound in the admixtures as compared to DMDMH.

Similar results were obtained when iodopropynyl alcohol (IPGA) was substituted for IPBC in the admixtures described above.

3. Preservative Activity (Challenge Test)

A typical cosmetic emulsion was prepared for microbiological challenge testing and predetermined admixtures of a methylol compound and IPBC were added at various use levels. The emulsion thus prepared had the following composition:

    ______________________________________                                                             % wt.                                                      ______________________________________                                         Phase A                                                                        Stearic Acid          5.00                                                     Mineral Oil           2.50                                                     Cetyl Alcohol         1.00                                                     Lareth-5 and Ceteth-5 and                                                                            0.50                                                     Oleth-5 and Steareth-5                                                         Glycerol Monostearate and                                                                            1.50                                                     Polyoxyethylene Stearate                                                       Phase B                                                                        Deionized Water       88.0                                                     Triethanolamine 99%   1.00                                                     Citric Acid 30% aqueous solution                                                                     0.60                                                     Preservative Admixture                                                                               qs                                                       ______________________________________                                    

To prepare the emulsion, Phases A and B were heated separately to 75°-80° C. Phase A then was added to Phase B with mixing. The mixture then was cooled to 55°-60° C. At this point the desired amount of the preservative admixture was added and the product was cooled to 50° C. while stirring. The citric acid solution then was added to adjust the pH and the mixture was stirred until a temperature of 30° C. was reached.

The challenge tests were carried out using the following microorganisms: SA, ECOLI, PSA, PC, AN and CAN, in this manner. 50 g. aliquots of the test emulsion containing various amounts of the preservative admixture were inoculated with approximately 10⁷ -10⁸ of the challenge organisms. The test samples then were stirred to disperse the challenge inoculum. The samples were incubated and assayed at 48 hours, 7, 14, 21 and 28 days. The assays were performed on 1 g. of the test sample by serially diluting 10¹ to 10⁶ of the original concentration. The plating medium for bacteria was Letheen agar and for fungi it was low pH Mycophil agar with Tween 20. Each plated sample was incubated for 48 hours at 37° C. for bacteria, 5 days at 25° C. for mold, and 3 days at 25° C. for fungi. After incubation, readings of the number of colonies per milliliter (cfu/ml) were made. At 21 days the test product was reinoculated with half of the original inoculum. The data is presented in Tables 15-23 below.

                  TABLE 15                                                         ______________________________________                                         2000:1 GERMALL ® II/IPBC                                                   ______________________________________                                         Test           48      7     14    21    28                                    Level Organism Hours   Days  Days  Days  Days                                  ______________________________________                                         0.01% AN       69,000  260,000                                                                              190,000                                                                              17,000                                                                               4,500                                 "     CAN      98,000  76,000                                                                               1,400 3,100 19,000                                "     ECOLI    110,000 290,000                                                                              2,400 138,000                                                                              560,000                               "     PC       <10     <10   <10   <10   <10                                   "     PSA      <10     <10   <10   <10   <10                                   "     SA       190,000 220   <10   <10   3,700                                 0.025%                                                                               AN       2,800   10    10    <10   220                                   "     CAN      58,000  29,000                                                                               18,000                                                                               56,000                                                                               110,000                               "     ECOLI    39,000  10    <10   <10   <10                                   "     PC       <10     <10   <10   <10   <10                                   "     PSA      <10     <10   <10   <10   <10                                   "     SA       37,000  170   <10   <10   <10                                   0.05% AN       20      <10   <10   <10   <10                                   "     CAN      19,000  6,600 70    <10   320                                   "     ECOLI    3,400   <10   <10   <10   <10                                   "     PC       <10     <10   <10   <10   <10                                   "     PSA      <10     <10   <10   <10   <10                                   "     SA       31,000  <10   <10   <10   <10                                   0.1%  AN       <10     <10   <10   <10   <10                                   "     CAN      180     <10   <10   <10   <10                                   "     ECOLI    <10     <10   <10   <10   <10                                   "     PC       <10     <10   <10   <10   <10                                   "     PSA      <10     <10   <10   <10   <10                                   "     SA       750     <10   <10   <10   <10                                   0.2%  AN       <10     <10   <10   <10   <10                                   "     CAN      <10     <10   <10   <10   <10                                   "     ECOLI    <10     <10   <10   <10   <10                                   "     PC       <10     <10   <10   <10   <10                                   "     PSA      <10     <10   <10   <10   <10                                   "     SA       <10     <10   <10   <10   <10                                   ______________________________________                                         Unpreserved control                                                            Organism                                                                              48 Hours 7 Days   14 Days                                                                               21 Days                                                                               28 Days                                 ______________________________________                                         AN     52,000   27,000   19,000 19,000 19,000                                  CAN    110,000  130,000  240,000                                                                               180,000                                                                               240,000                                 ECOLI  54,000   140,000  170,000                                                                               170,000                                                                               74,000                                  PC     6,400,000                                                                               6,400,000                                                                               2,000,000                                                                             6,700,000                                                                             29,000                                  PSA    110,000  700      110,000                                                                               290,000                                                                               85,000                                  SA     2,800,000                                                                               250,000  51,000 3,700  330                                     ______________________________________                                         Inoculum Concentration                                                         Organism       0 Hours  21 Days                                                ______________________________________                                         AN               26,000  53,000                                                CAN            1,000,000                                                                               1,900,000                                              ECOLI          3,600,000                                                                               170,000                                                PC             3,400,000                                                                                87,000                                                PSA            4,500,000                                                                               390,000                                                SA             4,100,000                                                                               200,000                                                ______________________________________                                    

                  TABLE 16                                                         ______________________________________                                         1000:1 GERMALL ® II/IPBC                                                   ______________________________________                                         Test           48      7     14    21    28                                    Level Organism Hours   Days  Days  Days  Days                                  ______________________________________                                         0.01% AN       34,000  3,500 80    10    <10                                   "     CAN      420,000 24,000                                                                               950   6,400 6,400,000                             "     ECOLI    120,000 63,000                                                                               93,000                                                                               92,000                                                                               9,600,000                             "     PC       10      25,000                                                                               1,600 15,800                                                                               33,000,000                            "     PSA      <10     <10   <10   <10   <10                                   "     SA       100,000 1,400 <10   <10   5,000                                 0.025%                                                                               AN       530     10    <10   <10   <10                                   "     CAN      34,000  750   10    770   240,000                               "     ECOLI    120,000 <10   <10   <10   <10                                   "     PC       <10     <10   <10   <10   <10                                   "     PSA      <10     <10   <10   <10   <10                                   "     SA       37,000  170   <10   <10   <10                                   0.05% AN       <10     <10   <10   <10   <10                                   "     CAN      13,000  <10   <10   <10   <10                                   "     ECOLI    68,000  <10   <10   <10   <10                                   "     PC       <10     <10   <10   <10   <10                                   "     PSA      <10     <10   <10   <10   <10                                   "     SA       21,000  <10   <10   <10   <10                                   0.1%  AN       <10     <10   <10   <10   <10                                   "     CAN      10      <10   <10   <10   <10                                   "     ECOLI    <10     <10   <10   <10   <10                                   "     PC       <10     <10   <10   <10   <10                                   "     PSA      <10     <10   <10   <10   <10                                   "     SA       1,400   <10   <10   <10   <10                                   0.2%  AN       <10     <10   <10   <10   <10                                   "     CAN      <10     <10   <10   <10   <10                                   "     ECOLI    <10     <10   <10   <10   <10                                   "     PC       <10     <10   <10   <10   <10                                   "     PSA      <10     <10   <10   <10   <10                                   "     SA       <ld     <10   <10   <10   <10                                   ______________________________________                                         Unpreserved control                                                            Organism                                                                              48 Hours 7 Days   14 Days                                                                               21 Days                                                                               28 Days                                 ______________________________________                                         AN     52,000   27,000   19,000 19,000 19,000                                  CAN    110,000  130,000  240,000                                                                               180,000                                                                               240,000                                 ECOLI  54,000   140,000  170,000                                                                               170,000                                                                               74,000                                  PC     6,400,000                                                                               6,400,000                                                                               2,000,000                                                                             6,700,000                                                                             29,000                                  PSA    110,000  700      110,000                                                                               290,000                                                                               85,000                                  SA     2,800,000                                                                               250,000  51,000 3,700  330                                     ______________________________________                                         Inoculum Concentration                                                         Organism       0 Hours  21 Days                                                ______________________________________                                         AN               26,000  53,000                                                CAN            1,000,000                                                                               1,900,000                                              ECOLI          3,600,000                                                                               170,000                                                PC             3,400,000                                                                                87,000                                                PSA            4,500,000                                                                               390,000                                                SA             4,100,000                                                                               200,000                                                ______________________________________                                    

                                      TABLE 17                                     __________________________________________________________________________     500:1 GERMALL® II/IPBC                                                     __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                             14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     0.01%  AN   23,000                                                                               40  <10  <10  <10                                            "      CAN  170,000                                                                              5,600                                                                              290  200  <10                                            "      ECOLI                                                                               90,000                                                                               57,000                                                                             95,000                                                                              70,000                                                                              240,000                                        "      PC   10    <10 <10  >10,000                                                                             42,000,000                                     "      PSA  <10   <10 <10  <10  <10                                            "      SA   380,000                                                                              440 <10  <10  5,100                                          __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                             14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     0.05%  AN   <10   <10 <10  <10  <10                                            "      CAN  8,700 <10 <10  <10  <10                                            "      ECOLI                                                                               60,000                                                                               <10 <10  <10  <10                                            "      PC   <10   <10 <10  <10  <10                                            "      PSA  <10   <10 <10  <10  <10                                            "      SA   31,000                                                                               <10 <10  <10  <10                                            __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                             14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     0.1%   AN   <10   <10 <10  <10  <10                                            "      CAN  <10   <10 <10  <10  <10                                            "      ECOLI                                                                               <10   <10 <10  <10  <10                                            "      PC   <10   <10 <10  <10  <10                                            "      PSA  <10   <10 <10  <10  <10                                            "      SA   890   <10 <10  <10  <10                                            __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                             14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     0.2%   AN   <10   <10 <10  <10  <10                                            "      CAN  <10   <10 <10  <10  <10                                            "      ECOLI                                                                               <10   <10 <10  <10  <10                                            "      PC   <10   <10 <10  <10  <10                                            "      PSA  <10   <10 <10  <10  <10                                            "      SA   <10   <10 <10  <10  <10                                            __________________________________________________________________________     Unpreserved control                                                            Organism   48 Hours                                                                             7 Days                                                                               14 Days                                                                             21 Days                                                                             28 Days                                       __________________________________________________________________________     AN         6,100 520,000                                                                              18,000                                                                              5,000                                                                               11,000                                        CAN        1,000,000                                                                            710,000                                                                              95,000                                                                              12,000                                                                              64,000                                        ECOLI      7,100,000                                                                            6,200,000                                                                            610,000                                                                             350,000                                                                             120,000                                       PC         14,600,000                                                                           160,000,000                                                                          3,600,000                                                                           2,720,000                                                                           9,500,000                                     PSA        20    900   130  4,100                                                                               >100,000                                      SA         43,000,000                                                                           600,000                                                                              1,000                                                                               220  <10                                           __________________________________________________________________________     Inoculum Concentration                                                         Organism         0 Hours                                                                             21 Days                                                  __________________________________________________________________________     AN               19,000                                                                              4,700,000                                                CAN              340,000                                                                             16,000,000                                               ECOLI            3,900,000                                                                           1,480,000                                                PC               3,800,000                                                                           1,380,000                                                PSA              9,200,000                                                                           730,000                                                  SA               4,800,000                                                                           360,000                                                  __________________________________________________________________________

                                      TABLE 18                                     __________________________________________________________________________     200:1 GERMALL ® II/IPBC                                                    __________________________________________________________________________     Test Level                                                                           Organism                                                                            48 Hours                                                                            7 Days                                                                              14 Days                                                                             21 Days                                                                             28 Days                                         __________________________________________________________________________     0.01% AN   47,000                                                                              320  10   <10  <10                                             "     CAN  810,000                                                                             450,000                                                                             410,000                                                                             190,000                                                                             63,000                                          "     ECOLI                                                                               220,000                                                                             7,600                                                                               <10  850  >1,000,000                                      "     PC   10,000                                                                              500,000                                                                             1,900,000                                                                           1,100,000                                                                           193,000                                         "     PSA  <10  <10  <10  <10  <10                                             "     SA   190,000                                                                             23,000                                                                              120  <10  <10                                             __________________________________________________________________________     Test Level                                                                           Organism                                                                            48 Hours                                                                            7 Days                                                                              14 Days                                                                             21 Days                                                                             28 Days                                         __________________________________________________________________________     0.05% AN   <10  <10  <10  <10  <10                                             "     CAN  190  <10  <10  <10  <10                                             "     ECOLI                                                                               37,000                                                                              <10  <10  <10  <10                                             "     PC   <10  <10  <10  <10  <10                                             "     PSA  <10  <10  <10  <10  <10                                             "     SA   19,000                                                                              <10  <10  <10  <10                                             __________________________________________________________________________     Test Level                                                                           Organism                                                                            48 Hours                                                                            7 Days                                                                              14 Days                                                                             21 Days                                                                             28 Days                                         __________________________________________________________________________     0.1%  AN   <10  <10  <10  <10  <10                                             "     CAN  10   <10  <10  <10  <10                                             "     ECOLI                                                                               <10  <10  <10  <10  <10                                             "     PC   <10  <10  <10  <10  <10                                             "     PSA  <10  <10  <10  <10  <10                                             "     SA   45,000                                                                              <10  <10  <10  <10                                             __________________________________________________________________________     Test Level                                                                           Organism                                                                            48 Hours                                                                            7 Days                                                                              14 Days                                                                             21 Days                                                                             28 Days                                         __________________________________________________________________________     0.2%  AN   <10  <10  <10  <10  <10                                             "     CAN  <10  <10  <10  <10  <10                                             "     ECOLI                                                                               <10  <10  <10  <10  <10                                             "     PC   <10  <10  <10  <10  <10                                             "     PSA  <10  <10  <10  <10  <10                                             "     SA   <10  <10  <10  <10  <10                                             __________________________________________________________________________     Unpreserved control                                                            Organism   48 Hours                                                                             7 Days                                                                              14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     AN         89,000                                                                               32,000                                                                              22,000                                                                              16,000                                                                              16,000                                         CAN        210,000                                                                              670,000                                                                             430,000                                                                             590,000                                                                             640,000                                        ECOLI      640,000                                                                              360,000                                                                             410,000                                                                             990,000                                                                             68,000                                         PC         19,000,000                                                                           3,200,000                                                                           7,000,000                                                                           >10,000                                                                             2,760,000                                      PSA        80    9,400                                                                               200,000                                                                             >10,000                                                                             34,000                                         SA         6,300,000                                                                            190,000                                                                             11,000                                                                              580  120                                            __________________________________________________________________________     Inoculum Concentration                                                         Organism         0 Hours                                                                             21 Days                                                  __________________________________________________________________________     AN               41,000                                                                              32,000                                                   CAN              640  1,100,000                                                ECOLI            5,800,000                                                                           1,300,000                                                PC               900,000                                                                             3,000,000                                                PSA              1,800,000                                                                           4,900,000                                                SA               7,200,000                                                                           2,000,000                                                __________________________________________________________________________

                                      TABLE 19                                     __________________________________________________________________________     50:1 GERMALL ® II/IPBC                                                     __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                             14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     0.01%  AN   4,100 40  <10  <10  <10                                            "      CAN  310,000                                                                              7,700                                                                              560  5,600                                                                               5,200                                          "      ECOLI                                                                               170,000                                                                              710 10   <10  120                                            "      PC   7,400 74,000                                                                             340,000                                                                             720,000                                                                             520,000                                        "      PSA  <10   <10 <10  <10  30                                             "      SA   110,000                                                                              11,000                                                                             <10  <10  9,200                                          __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                             14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     0.05%  AN   <10   100 <10  <10  <10                                            "      CAN  210   <10 <10  <10  <10                                            "      ECOLI                                                                               150,000                                                                              <10 <10  <10  <10                                            "      PC   <10   <10 <10  <10  <10                                            "      PSA  <10   <10 <10  <10  <10                                            "      SA   35,000                                                                               <10 <10  <10  <10                                            __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                             14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     0.1%   AN   <10   <10 <10  <10  <10                                            "      CAN  <10   <10 <10  <10  <10                                            "      ECOLI                                                                               510   <10 <10  <10  <10                                            "      PC   <10   <10 <10  <10  <10                                            "      PSA  <10   <10 <10  <10  <10                                            "      SA   3,000 <10 <10  <10  <10                                            __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                             14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     0.2%   AN   <10   <10 <10  <10  <10                                            "      CAN  <10   <10 <10  <10  <10                                            "      ECOLI                                                                               <10   <10 <10  <10  <10                                            "      PC   <10   <10 <10  <10  <10                                            "      PSA  <10   <10 <10  <10  <10                                            "      SA   <10   <10 <10  <10  <10                                            __________________________________________________________________________     Unpreserved control                                                            Organism   48 Hours                                                                             7 Days                                                                              14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     AN         89,000                                                                               32,000                                                                              22,000                                                                              16,000                                                                              16,000                                         CAN        210,000                                                                              670,000                                                                             430,000                                                                             590,000                                                                             640,000                                        ECOLI      640,000                                                                              360,000                                                                             410,000                                                                             990,000                                                                             68,000                                         PC         19,000,000                                                                           3,200,000                                                                           7,000,000                                                                           >10,000                                                                             2,760,000                                      PSA        80    9,400                                                                               200,000                                                                             >10,000                                                                             34,000                                         SA         6,300,000                                                                            190,000                                                                             11,000                                                                              580  120                                            __________________________________________________________________________     Inoculum Concentration                                                         Organism         0 Hours                                                                             21 Days                                                  __________________________________________________________________________     AN               41,000                                                                              32,000                                                   CAN              640  1,100,000                                                ECOLI            5,800,000                                                                           1,300,000                                                PC               900,000                                                                             3,000,000                                                PSA              1,800,000                                                                           4,900,000                                                SA               7,200,000                                                                           2,000,000                                                __________________________________________________________________________

                                      TABLE 20                                     __________________________________________________________________________     20:1 GERMALL ® II/IPBC                                                     __________________________________________________________________________     Test Level                                                                           Organism                                                                            48 Hours                                                                            7 Days                                                                              14 Days                                                                             21 Days                                                                              28 Days                                        __________________________________________________________________________     0.01% AN   3,100                                                                               <10  <10  <10   <10                                            "     CAN  75,000                                                                              220  <10  <10   2,400                                          "     ECOLI                                                                               160,000                                                                             110  <10  <10   20                                             "     PC   12,000                                                                              1,000,000                                                                           2,100,000                                                                           >1,000,000                                                                           730,000                                        "     PSA  <10  <10  <10  <10   4,000                                          "     SA   140,000                                                                             4,100                                                                               <10  <10   1,680                                          __________________________________________________________________________     Test Level                                                                           Organism                                                                            48 Hours                                                                            7 Days                                                                              14 Days                                                                             21 Days                                                                              28 Days                                        __________________________________________________________________________     0.05% AN   <10  <10  <10  <10   <10                                            "     CAN  <10  <10  <10  <10   <10                                            "     ECOLI                                                                               16,000                                                                              <10  <10  <10   <10                                            "     PC   <10  <10  <10  <10   <10                                            "     PSA  <10  <10       <10   <10                                            "     SA   31,000                                                                              <10  <10  <10   <10                                            __________________________________________________________________________     Test Level                                                                           Organism                                                                            48 Hours                                                                            7 Days                                                                              14 Days                                                                             21 Days                                                                              28 Days                                        __________________________________________________________________________     0.1%  AN   <10  <10  <10  <10   <10                                            "     CAN  <10  <10  <10  <10   <10                                            "     ECOLI                                                                               <10  <10  <10  <10   <10                                            "     PC   <10  <10  <10  <10   <10                                            "     PSA  <10  <10  <10  <10   <10                                            "     SA   6,800                                                                               <10  <10  <10   <10                                            __________________________________________________________________________     Test Level                                                                           Organism                                                                            48 Hours                                                                            7 Days                                                                              14 Days                                                                             21 Days                                                                              28 Days                                        __________________________________________________________________________     0.2%  AN   <10  <10  <10  <10   <10                                            "     CAN  <10  <10  <10  <10   <10                                            "     ECOLI                                                                               <10  <10  <10  <10   <10                                            "     PC   <10  <10  <10  <10   <10                                            "     PSA  <10  <10  <10  <10   <10                                            "     SA   <10  <10  <10  <10   <10                                            __________________________________________________________________________     Unpreserved control                                                            Organism   48 Hours                                                                             7 Days                                                                              14 Days                                                                             21 Days                                                                             28 Days                                        __________________________________________________________________________     AN         89,000                                                                               32,000                                                                              22,000                                                                              16,000                                                                              16,000                                         CAN        210,000                                                                              670,000                                                                             430,000                                                                             590,000                                                                             640,000                                        ECOLI      640,000                                                                              360,000                                                                             410,000                                                                             990,000                                                                             68,000                                         PC         19,000,000                                                                           3,200,000                                                                           7,000,000                                                                           >10,000                                                                             2,760,000                                      PSA        80    9,400                                                                               200,000                                                                             >10,000                                                                             34,000                                         SA         6,300,000                                                                            190,000                                                                             11,000                                                                              580  120                                            __________________________________________________________________________     Inoculum Concentration                                                         Organism         0 Hours                                                                             21 Days                                                  __________________________________________________________________________     AN               41,000                                                                              32,000                                                   CAN              640  1,100,000                                                ECOLI            5,800,000                                                                           1,300,000                                                PC               900,000                                                                             3,000,000                                                PSA              1,800,000                                                                           4,900,000                                                SA               7,200,000                                                                           2,000,000                                                __________________________________________________________________________

                                      TABLE 21                                     __________________________________________________________________________     2000:1 DMDMH/IPBC                                                              __________________________________________________________________________     Test Level                                                                           Organism                                                                             48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                              28 Days                                      __________________________________________________________________________     0.025%                                                                               AN    4,100                                                                               38,000                                                                               270  80    100                                          "     CAN   270,000                                                                             1,900,000                                                                            550,000                                                                             220,000                                                                              210,000                                      "     ECOLI 1,300,000                                                                           <10   <10  <10   3,000                                        "     PC    <10  <10   <10  <10   <10                                          "     PSA   <10  <10   <10  <10   <10                                          "     SA    42,000                                                                              20    <10  <10   <10                                          __________________________________________________________________________     Test Level                                                                           Organism                                                                             48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                              28 Days                                      __________________________________________________________________________     0.05% AN    <10  <10   <10  <10   <10                                          "     CAN   770,000                                                                             130,000                                                                              670,000                                                                             160,000                                                                              64,000                                       "     ECOLI 220,000                                                                             <10   <10  <10   <10                                          "     PC    <10  <10   <10  <10   <10                                          "     PSA   <10  <10   <10  <10   <10                                          "     SA    9,000                                                                               <10   <10  <10   <10                                          __________________________________________________________________________     Test Level                                                                           Organism                                                                             48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                              28 Days                                      __________________________________________________________________________     0.1%  AN    <10  <10   <10  <10   <10                                          "     CAN   580  840   500  40,000                                                                               83,000                                       "     ECOLI 340  <10   <10  <10   <10                                          "     PC    <10  <10   <10  <10   <10                                          "     PSA   <10  <10   <10  <10   <10                                          "     SA    29,000                                                                              <10   <10  <10   <10                                          __________________________________________________________________________     Test Level                                                                           Organism                                                                             48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                              28 Days                                      __________________________________________________________________________     0.2%  AN    <10  <10   <10  <10   <10                                          "     CAN   <10  10    10   <10   21                                           "     ECOLI <10  <10   <10  <10   <10                                          "     PC    <10  <10   <10  <10   <10                                          "     PSA   <10  <10   <10  <10   <10                                          "     SA    <10  <10   <10  <10   <10                                          __________________________________________________________________________     Unpreserved control                                                            Organism   48 Hours                                                                             7 Days                                                                               14 Days                                                                             21 Days                                                                             28 Days                                       __________________________________________________________________________     AN         37,000                                                                               36,000                                                                               24,000                                                                              5,200                                                                               6,000                                         CAN        120,000                                                                              1,900,000                                                                            3,300,000                                                                           480,000                                                                             790,000                                       ECOLI      150,000                                                                              2,500,000                                                                            7,300,000                                                                           240,000                                                                             140,000                                       PC         19,000,000                                                                           15,600,000                                                                           5,900,000                                                                           8,500,000                                                                           31,000,000                                    PSA        <10   <10   100  15,200                                                                              300,000                                       SA         7,000,000                                                                            >1,000,000                                                                           12,000                                                                              3,000                                                                               110                                           __________________________________________________________________________     Inoculum Concentration                                                         Organism          0 Hours                                                                             21 Days                                                 __________________________________________________________________________     AN                50,000                                                                              41,000                                                  CAN               1,400,000                                                                           640                                                     ECOLI             4,800,000                                                                           5,800,000                                               PC                9,200,000                                                                           900,000                                                 PSA               6,900,000                                                                           9,000,000                                               SA                5,700,000                                                                           7,200,000                                               __________________________________________________________________________

                                      TABLE 22                                     __________________________________________________________________________     1000:1 DMDMH/IPBC                                                              __________________________________________________________________________     Test Level                                                                           Organism                                                                             48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                              28 Days                                      __________________________________________________________________________     0.025%                                                                               AN    650  900   <10  <10   140                                          "     CAN   97,000                                                                              900,000                                                                              2,300,000                                                                           120,000                                                                              120,000                                      "     ECOLI 160,000                                                                             <10   <10  <10   2,400                                        "     PC    <10  <10   <10  <10   <10                                          "     PSA   <10  <10   <10  <10   <10                                          "     SA    23,000                                                                              <10   <10  <10   90                                           __________________________________________________________________________     Test Level                                                                           Organism                                                                             48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                              28 Days                                      __________________________________________________________________________     0.05% AN    20   <10   <10  <10   <10                                          "     CAN   65,000                                                                              520,000                                                                              56,000                                                                              32,000                                                                               370,000                                      "     ECOLI 26,000                                                                              <10   <10  <10   <10                                          "     PC    <10  <10   <10  <10   <10                                          "     PSA   <10  <10   <10  <10   <10                                          "     SA    12,000                                                                              <10   <10  <10   <10                                          __________________________________________________________________________     Test Level                                                                           Organism                                                                             48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                              28 Days                                      __________________________________________________________________________     0.1%  AN    <10  <10   <10  <10   <10                                          "     CAN   3,100                                                                               4,800 180  640   4,400                                        "     ECOLI 45,000                                                                              <10   <10  <10   <10                                          "     PC    <10  <10   <10  <10   <10                                          "     PSA   <10  <10   <10  <10   <10                                          "     SA    6,000                                                                               <10   <10  <10   <10                                          __________________________________________________________________________     Test Level                                                                           Organism                                                                             48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                              28 Days                                      __________________________________________________________________________     0.2%  AN    <10  <10   <10  <10   <10                                          "     CAN   <10  <10   <10  <10   <10                                          "     ECOLI <10  <10   <10  <10   <10                                          "     PC    <10  <10   <10  <10   <10                                          "     PSA   <10  <10   <10  <10   <10                                          "     SA    180  <10   <10  <10   <10                                          __________________________________________________________________________     Unpreserved control                                                            Organism   48 Hours                                                                             7 Days                                                                               14 Days                                                                             21 Days                                                                             28 Days                                       __________________________________________________________________________     AN         37,000                                                                               36,000                                                                               24,000                                                                              5,200                                                                               6,000                                         CAN        120,000                                                                              1,900,000                                                                            3,300,000                                                                           480,000                                                                             790,000                                       ECOLI      150,000                                                                              2,500,000                                                                            7,300,000                                                                           240,000                                                                             140,000                                       PC         19,000,000                                                                           15,600,000                                                                           5,900,000                                                                           8,500,000                                                                           31,000,000                                    PSA        <10   <10   100  15,200                                                                              300,000                                       SA         7,000,000                                                                            >1,000,000                                                                           12,000                                                                              3,000                                                                               110                                           __________________________________________________________________________     Inoculum Concentration                                                         Organism          0 Hours                                                                             21 Days                                                 __________________________________________________________________________     AN                50,000                                                                              41,000                                                  CAN               1,400,000                                                                           640                                                     ECOLI             4,800,000                                                                           5,800,000                                               PC                9,200,000                                                                           900,000                                                 PSA               6,900,000                                                                           9,000,000                                               SA                5,700,000                                                                           7,200,000                                               __________________________________________________________________________

                                      TABLE 23                                     __________________________________________________________________________     2000:1 GADM/IPBC                                                               __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                              14 Days                                                                              21 Days                                                                             28 Days                                      __________________________________________________________________________     0.025% AN   300   21   10    <10  11                                           "      CAN  480,000                                                                              890,000                                                                             940,000                                                                              1,040,000                                                                           130,000                                      "      ECOLI                                                                               230,000                                                                              <10  <10   <10  <10                                          "      PC   <10   <10  <10   <10  <10                                          "      PSA  <10   <10  <10   <10  <10                                          "      SA   78,000                                                                               <10  <10   <10  <10                                          __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                              14 Days                                                                              21 Days                                                                             28 Days                                      __________________________________________________________________________     0.05%  AN   <10   <10  <10   <10  <10                                          "      CAN  110,000                                                                              4,100,000                                                                           3,600,000                                                                            330,000                                                                             97,000                                       "      ECOLI                                                                               120,000                                                                              <10  <10   <10  <10                                          "      PC   <10   <10  <10   <10  <10                                          "      PSA  <10   <10  <10   <10  <10                                          "      SA   56,000                                                                               <10  <10   <10  <10                                          __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                              14 Days                                                                              21 Days                                                                             28 Days                                      __________________________________________________________________________     0.1%   AN   <10   <10  <10   <10  <10                                          "      CAN  1,200,000                                                                            53,000                                                                              430,000                                                                              144,000                                                                             110,000                                      "      ECOLI                                                                               <10   <10  <10   <10  <10                                          "      PC   <10   <10  <10   <10  <10                                          "      PSA  <10   <10  <10   <10  <10                                          "      SA   <10   <10  <10   <10  <10                                          __________________________________________________________________________     Test Level                                                                            Organism                                                                            48 Hours                                                                             7 Days                                                                              14 Days                                                                              21 Days                                                                             28 Days                                      __________________________________________________________________________     0.2%   AN   <10   <10  <10   <10  <10                                          "      CAN  90,000                                                                               <10  <10   <10  60                                           "      ECOLI                                                                               <10   <10  <10   <10  <10                                          "      PC   <10   <10  <10   <10  <10                                          "      PSA  <10   <10  <10   <10  <10                                          "      SA   <10   <10  <10   <10  <10                                          __________________________________________________________________________     Unpreserved control                                                            Organism   48 Hours                                                                             7 Days                                                                               14 Days                                                                              21 Days                                                                              28 Days                                     __________________________________________________________________________     AN         50,000                                                                               33,000                                                                               33,000                                                                               13,000                                                                               5,400                                       CAN        780,000                                                                              780,000                                                                              780,000                                                                              500,000                                                                              170,000                                     ECOLI      600,000                                                                              3,100,000                                                                            920,000                                                                              920,000                                                                              140,000                                     PC         11,000,000                                                                           30,000,000                                                                           10,000,000                                                                           10,000,000                                                                           1,400,000                                   PSA        3,800 600   12,800                                                                               12,800                                                                               100,000                                     SA         14,000,000                                                                           410,000                                                                              7,100 7,100 80                                          __________________________________________________________________________     Inoculum Concentration                                                         Organism          0 Hours                                                                             21 Days                                                 __________________________________________________________________________     AN                53,000                                                                              10,000                                                  CAN               1,900,000                                                                           310,000                                                 ECOLI             170,000                                                                             3,500,000                                               PC                87,000                                                                              2,500,000                                               PSA               390,000                                                                             5,400,000                                               SA                200,000                                                                             4,100,000                                               __________________________________________________________________________

Discussion of Challenge Testing Results

The 28-day challenge results reported in Tables 15-23 above demonstrate the effectiveness of the preservative admixture of the invention in a use emulsion composition against a wide range of bacteria and fungi organisms.

For example, admixture compositions of Germall® II and IPBC at a wt. ratio of 2000:1 (Table 15), when present at use levels of 0.05 to 0.2%, corresponding to 0.75 to 10 ppm IPBC and 500 to 2000 ppm methylol levels, provide substantially complete protection against all tested organisms after 28 days. At the low use level of 0.05% active, all the challenge tests passed within 21 days. Then, upon reinoculation after 21 days, all organisms died within 7 days except CAN which cleared within 14 days.

Table 21 shows the challenge test results for DMDMH and IPBC admixtures at the same 2000:1 wt. ratio. A use level of 0.2%, however, is needed for this blend to pass against all organisms after 21 days. Upon reinoculation, all organisms died within 7 days with the exception of CAN which cleared within 14 days. It is thus evident from these results that Germall® II blended with IPBC is 4 times more effective than a DMDMH/IPBC blend.

Germall® II also is superior to GADM as the methylol compound, as shown in Table 23.

Table 24 below is a study of the activity of solution of GII/IPBC in propylene glycol. The admixtures of the active GII and IPBC components were prepared at weight ratios of 99.5%/0.5% and 99%/1%, and added to 60% by weight propylene glycol. The resulting solutions were tested at 0.05%, 0.1% and 0.2% total active in a proteinaceous shampoo formulation.

                                      TABLE 24                                     __________________________________________________________________________     99.5% GII/0.5% IPBC/propylene glycol solution - 0.05% total active             Test Level                                                                            Organism                                                                            48 Hours                                                                              7 Days                                                                             14 Days 21 Days                                                                             28 Days                                    __________________________________________________________________________     0.05%  AN   310,000                                                                               2,000                                                                              <10     <10  <10                                        "      CAN  44,000 2,400                                                                              <10     <10  1,800                                      "      ECOLI                                                                               3,000  <10 <10     <10  <10                                        "      PC   400,000                                                                               62,000                                                                             90      <10  >10,000                                    "      PSA  5,300,000                                                                             3,000                                                                              <10     <10  >10,000                                    "      SA   10     10  <10     <10  <10                                        __________________________________________________________________________     99.5% GII/0.5% IPBC/propylene glycol solution - 0.1% total active              Test Level                                                                            Organism                                                                            48 Hours                                                                              7 Days                                                                             14 Days 21 Days                                                                             28 Days                                    __________________________________________________________________________     0.1%   AN   210,000                                                                               <10 <10     <10  <10                                        "      CAN  1,500  <10 <10     <10  <10                                        "      ECOLI                                                                               580    <10 <10     <10  20                                         "      PC   34,000 <10 <10     <10  <10                                        "      PSA  780    <10 <10     <10  <10                                        "      SA   <10    <10 <10     <10  <10                                        __________________________________________________________________________     99.5% GII/0.5% IPBC/propylene glycol solution - 0.2% total active              Test Level                                                                            Organism                                                                            48 Hours                                                                              7 Days                                                                             14 Days 21 Days                                                                             28 Days                                    __________________________________________________________________________     0.2%   AN   <10    <10 <10     <10  <10                                        "      CAN  <10    <10 <10     <10  <10                                        "      ECOLI                                                                               <10    <10 <10     <10  <10                                        "      PC   <10    <10 <10     <10  <10                                        "      PSA  <10    <10 <10     <10  <10                                        "      SA   <10    <10 <10     <10  <10                                        __________________________________________________________________________     99% GII/1% IPBC/propylene glycol solution - 0.05% total active                 Test Level                                                                            Organism                                                                            48 Hours                                                                              7 Days                                                                             14 Days 21 Days                                                                             28 Days                                    __________________________________________________________________________     0.05%  AN   89,000 <10 <10     <10  <10                                        "      CAN  4,400  <10 <10     <10  20                                         "      ECOLI                                                                               3,300  <10 <10     <10  60                                         "      PC   260,000                                                                               <10 <10     <10  3,400                                      "      PSA  64,000 <10 <10     <10  280                                        "      SA   <10    <10 <10     <10  <10                                        __________________________________________________________________________     99% GII/1% IPBC/propylene glycol solution - 0.1% total active                  Test Level                                                                            Organism                                                                            48 Hours                                                                              7 Days                                                                             14 Days 21 Days                                                                             28 Days                                    __________________________________________________________________________     0.1%   AN   37,000 <10 <10     <10  <10                                        "      CAN  <10    <10 <10     <10  <10                                        "      ECOLI                                                                               840    <10 <10     <10  <10                                        "      PC   48,000 <10 <10     <10  <10                                        "      PSA  440    <10 <10     <10  <10                                        "      SA   <10    <10 <10     <10  <10                                        __________________________________________________________________________     99% GII/1% IPBC/propylene glycol solution - 0.2% total active                  Test Level                                                                            Organism                                                                            48 Hours                                                                              7 Days                                                                             14 Days 21 Days                                                                             28 Days                                    __________________________________________________________________________     0.2%   AN   <10    <10 <10     <10  <10                                        "      CAN  <10    <10 <10     <10  <10                                        "      ECOLI                                                                               <10    <10 <10     <10  <10                                        "      PC   <10    <10 <10     <10  <10                                        "      PSA  <10    <10 <10     <10  <10                                        "      SA   <10    <10 <10     <10  <10                                        __________________________________________________________________________     Unpreserved control                                                            Organism   48 Hours                                                                              7 Days 14 Days                                                                              21 Days                                                                               28 Days                                  __________________________________________________________________________     AN         4,000,000                                                           CAN        160,000                                                                               >100,000,000                                                                          5,600,000                                                                            >100,000,000                                                                          >1,000,000                               ECOLI             >100,000,000                                                                          800,000,000                                                                          48,000,000                                                                            600,000                                  PC         >100,000,000                                                                          50,000,000                                                                            48,000,000   >1,000,000                               PSA        >100,000,000                                                                          >100,000,000                                                                          58,000,000                                                                           65,000,000                                                                            >1,000,000                               SA                >100,000,000                                                 __________________________________________________________________________     Inoculum Concentration                                                         Organism           0 Hours                                                                              21 Days                                               __________________________________________________________________________     AN                 380,000                                                                             330,000                                                CAN                860,000                                                                             4,200,000                                              ECOLI              2,500,000                                                                           5,300,000                                              PC                 1,900,000                                                                           60,000,000                                             PSA                3,200,000                                                                           5,000,000                                              SA                 2,400,000                                                                           3,000,000                                              __________________________________________________________________________

Table 25 shows a similar study as in Table 24 above in which the vehicle for the composition was the typical emulsion described above.

                                      TABLE 25                                     __________________________________________________________________________     99.5% GII/0.5% IPBC/propylene glycol solution - 0.05% total active             Test Level                                                                           Organism                                                                              48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                               28 Days                                    __________________________________________________________________________     0.05% AN     40   <10   <10  <10    <10                                        "     CAN    520,000                                                                             <10   <10  <10    <10                                        "     ECOLI  320  <10   <10  <10    <10                                        "     PC     <10  <10   <10  <10    <10                                        "     PSA    <10  <10   <10  <10    <10                                        "     SA     24,000                                                                              <10   <10  <10    <10                                        __________________________________________________________________________     99.5% GII/0.5% IPBC/propylene glycol solution - 0.1% total active              Test Level                                                                           Organism                                                                              48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                               28 Days                                    __________________________________________________________________________     0.1%  AN     <10  <10   <10  <10    <10                                        "     CAN    <10  <10   <10  <10    <10                                        "     ECOLI  10   <10   <10  <10    <10                                        "     PC     <10  <10   <10  <10    <10                                        "     PSA    <10  <10   <10  <10    <10                                        "     SA     650  <10   <10  <10    <10                                        __________________________________________________________________________     99.5% GII/0.5% IPBC/propylene glycol solution - 0.2% total active              Test Level                                                                           Organism                                                                              48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                               28 Days                                    __________________________________________________________________________     0.2%  AN     <10  <10   <10  <10    <10                                        "     CAN    <10  <10   <10  <10    <10                                        "     ECOLI  <10  <10   <10  <10    <10                                        "     PC     <10  <10   <10  <10    <10                                        "     PSA    <10  <10   <10  <10    <10                                        "     SA     <10  <10   <10  <10    <10                                        __________________________________________________________________________     99% GII/1% IPBC/propylene glycol solution - 0.05% total active                 Test Level                                                                           Organism                                                                              48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                               28 Days                                    __________________________________________________________________________     0.05% AN     <10  <10   <10  <10    <10                                        "     CAN    6,700                                                                               <10   <10  <10    <10                                        "     ECOLI  66,000                                                                              <10   <10  <10    <10                                        "     PC     <10  <10   <10  <10    <10                                        "     PSA    <10  <10   <10  <10    <10                                        "     SA     50,000                                                                              <10   <10  <10    <10                                        __________________________________________________________________________     99% GII/1% IPBC/propylene glycol solution - 0.1% total active                  Test Level                                                                           Organism                                                                              48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                               28 Days                                    __________________________________________________________________________     0.1%  AN     <10  <10   <10  <10    <10                                        "     CAN    <10  <10   <10  <10    <10                                        "     ECOLI  <10  <10   <10  <10    <10                                        "     PC     <10  <10   <10  <10    <10                                        "     PSA    <10  <10   <10  <10    <10                                        "     SA     620  <10   <10  <10    <10                                        __________________________________________________________________________     99% GII/1% IPBC/propylene glycol solution - 0.2% total active                  Test Level                                                                           Organism                                                                              48 Hours                                                                            7 Days                                                                               14 Days                                                                             21 Days                                                                               28 Days                                    __________________________________________________________________________     0.2%  AN     <10  <10   <10  <10    <10                                        "     CAN    <10  <10   <10  <10    <10                                        "     ECOLI  <10  <10   <10  <10    <10                                        "     PC     <10  <10   <10  <10    <10                                        "     PSA    <10  <10   <10  <10    <10                                        "     SA     <10  <10   <10  <10    <10                                        __________________________________________________________________________     Unpreserved control                                                            Organism   48 Hours                                                                             7 Days                                                                               14 Days                                                                              21 Days                                                                              28 Days                                     __________________________________________________________________________     AN         3,100,000                                                                            650,000                                                                              370,000                                                                              1,400,000                                                                            260,000                                     CAN        6,000,000                                                                            4,000,000                                                                            1,100,000                                                                            5,800,000                                                                            >1,000,000                                  ECOLI      11,000,000                                                                           7,300,000                                                                            6,000,000                                                                            730,000                                                                              220,000                                     PC         100,000,000                                                                          53,000,000                                                                           40,000,000                                                                           40,000,000                                                                           600,000                                     PSA        5,000,000                                                                            500,000                                                                              2,700,000                                                                            72,000                                                                               20,000                                      SA         30,000,000                                                                           150,000                                                                              440,000                                                                              2,500 9,900                                       __________________________________________________________________________     Inoculum Concentration                                                         Organism          0 Hours                                                                             21 Days                                                 __________________________________________________________________________     AN                380,000                                                                             330,000                                                 CAN               860,000                                                                             4,200,000                                               ECOLI             2,500,000                                                                           5,300,000                                               PC                1,900,000                                                                           60,000,000                                              PSA               3,200,000                                                                           5,000,000                                               SA                2,400,000                                                                           3,000,000                                               __________________________________________________________________________

The results shown in Tables 24 and 25 demonstrate that the compositions of the invention are completely effective against the tested organisms in comparison to the unpreserved controls.

While the invention has been described with particular reference to certain embodiments thereof, it will be understood that changes and modifications may be made which are within the skill of the art. Accordingly, it is intended to be bound only by the following claims, in which: 

What is claimed is:
 1. A water soluble preservative antimicrobial composition for addition to commercial use products at predetermined use levels to provide synergistic biocidal activity against a wide range of fungi and gram-negative and gram-positive bacteria, comprising an active liquid blend of(1) an admixture of(a) N-[1,3-bis (hydroxymethyl)-2,5-dioxo-4-imidazolidinyl]-N,N'-bis (hydroxymethyl) urea; and (b) 3-iodo-2-propynylbutyl carbamate, in a weight ratio of (a):(b) of 100:1 to 2000:1, and (2) propylene glycol or 1,3-butylene glycol.
 2. A water soluble preservative antimicrobial composition according to claim 1 wherein said weight ratio is 200:1 to 500:1.
 3. A water soluble preservative antimicrobial composition according to claim 1 which comprises about 20 to 55 weight percent of (1) and 45 to 80 weight percent of (2).
 4. A composition according to claim 3 which comprises about 40 weight percent of (1) and about 60 weight percent of (2).
 5. A commercial use product which is protected for an extended period of time against contamination by a wide range of fungi and gram-negative and gram-positive bacteria which includes 0.1 to 5% by weight of the composition of claim
 1. 6. A product according to claim 5 which includes about 0.5 to 1% by weight of the composition of claim
 1. 7. A commercial use product according to claim 5 which is a personal care, household or industrial composition.
 8. A commercial use product according to claim 5 which is a shampoo. 